Yield:471-53-4 250 mg

Reaction Conditions:

with sulfuric acid in methanolReflux;

Steps:

Acidic hydrolysis of GL to GA
GL (650.0mg obtained from Flash chromatographic fractions42-58) was dissolved in 25 ml of 10% H2SO4 solution inMeOH, and the reaction mixture was refluxed for 3-4h,which was further diluted with water, neutralised with 10%NaOH solution and then extracted thrice with CHCl3. Thecombined CHCl3 extract was dried under vacuum, whichafforded aglycone (450 mg). This aglycone was purified overflash using silica gel-H. A total of 148 fractions were collected and pooled based on their TLC profile. The fractions 29-46eluted with CHCl3 MeOH (99:1) afforded homogeneous product(GA, 250 mg) characterised as GA on the basis of their 1Hand 13C NMR spectroscopic data, 18b-GA (Figure 3).

References:

Shukla, Aparna;Tyagi, Rekha;Meena, Sanjeev;Datta, Dipak;Srivastava, Santosh Kumar;Khan, Feroz [Journal of Biomolecular Structure and Dynamics,2020,vol. 38,# 1,p. 168 - 185]